I believe I got everything for Zern, now on to the Naga, 

I decided to drop skill points for races and also be aware that you will get 2 HD per level, one from class one from level, I am making a particular note of this due to the Zern's warping energy ability.

Zern
HD: d6 

Level 1: +2 Dex, +2 int, Darkvision 60ft, +1 Natural Armor, Spell Resistance 3, Warping Energy, (1d6 per 2 HD + Int modifier), Craft (Flesh Sculpting)
Level 2: +2 Str, +2 Con, +1 Natural Armor, Fast Healing 1, Spell Resistance 6, Adaptive Defenses, Gaseous Form (1/day)
Level 3: +2 Dex, +2 Wis, +1 Natural Armor, Fast Healing 2, Spell Resistance 9, Transmutation affinity
Level 4: +2 Str +2 Int, +1 Natural Armor, Fast Healing 3, Spell Resistance 12, Reduce Person (3 per day)
Level 5: +2 Dex, +2 Con, +1 Natural Armor, Fast Healing 4, Spell Resistance 15, Shifting Guise, Baleful Polymorph (1/day)
Level 6: +2 Str, +1 Natural Armor, Fast Healing 5, Spell Resistance 18, Malleable form (At will), Reduce Person (at will)